1. Field of the Invention
The present invention relates generally to power saving, and more particularly to, a method and related apparatus for controlling an operational status of an electronic device and determine whether to wake up the electronic device in the power saving mode.
2. Description of the Prior Art
Power consumption is an important consideration when designing of modern electronic devices. In order to reduce power consumption, many electronic devices, such as portable devices, TVs, monitors, and the like, can operate in a normal mode and a power saving mode. In the power saving mode, most circuit components of the electronic device are temporarily shut down to reduce the power consumption. In this regards, a detect mechanism/circuit is needed to determine whether to wake up the electronic device from the power saving mode in order to re-activate the circuit components that are temporarily shut down, thereby configuring the electronic device to operate in the normal mode.
Some of the electronic devices, such as high definition multimedia interface (HDMI) appliances (e.g. HDMI sinks), use clock-detect mechanisms/circuits to determine whether to be woken up from the power saving mode if an external clock input is received (from HDMI sources). Once receiving the external clock input, the clock-detect mechanisms/circuits of the HDMI sinks may accordingly send an interrupt to a microcontroller to recover the function of a data decoder. The data decoder will determine whether any valid data is simultaneously received. If yes, it represents that the HDMI sinks needs to be operated in the normal mode for processing the valid data transmitted from the HDMI sources, and thus the HDMI sinks will be woken up.
However, in some cases, HDMI transmitters of the HDMI sources may send the HDMI sinks a meaningless clock signal on a clock channel of HDMI link coupled therebetween, but no valid data is received on data channel(s) of HDMI link by the HDMI sinks. This may be because the HDMI transmitter is interfered with noises or is improperly designed. In this situation, the data decoder may be mistakenly re-activated for decoding the data signals received in the data channel. However, since there is no valid data in the data chancel, it leads to unnecessary power consumption. Therefore, the conventional clock-detect mechanisms/circuits of waking up the electronic devices from the power saving mode have some advantages that need to be improved.